基于动态拓扑调整的含构网型变流器系统暂态稳定性提升方法OA

Insufficient voltage support during faults in grid-forming(GFM)converters leads to a sharp decline in electromagnetic power,resulting in frequent transient power angle stability issues in systems with GFM converters.There is an urgent need for a control method that can rapidly enhance power transmission capability during faults.The advent of advanced circuit breakers with millisecond-level response capabilities provides the necessary equipment support for improving transient stability through dynamic topology adjustment.To address this,this paper proposes a method to enhance transient stability based on dynamic grid topology adjustment,effectively mitigating power angle instability in systems with GFM converters.First,the transient stability problem of systems with GFM converters is modeled.By analyzing the impact of disconnecting the line between the power source and the fault point on the equivalent reactance,the fundamental principle of how dynamic topology adjustment enhances the power transmission capability of loop networks is explained.Furthermore,the mechanism by which dynamic topology adjustment improves the transient stability of systems with GFM converters is analyzed using the equal area criterion and phase portrait method.Finally,multi-scenario simulation results based on the IEEE 39-bus system demonstrate that the proposed method effectively enhances power angle stability under different fault locations and renewable energy penetration levels,offering a novel emergency control strategy for power grids with a high proportion of renewable energy.